Thrombocytopenia, vasculitis, "senile" purpura, and scurvy. Thrombocytopenia ITPTTPHereditary: ADAMTS-13 activity assay Vasculitis Classified according to histological findings at biopsy; RFTs and LFTs reflect extent of disease; disease activity relates to CRP, ESR, ± Complement C3 and C4 Systemic necrotising: Antineutrophilic cytoplasmic Ab (ANCA)†Polyarteritis nodosa (2-30 cases per million) – systemic necrotising vasculitis of middle-age (peaks … Continue reading Causes of Purpura*